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1.
Antonie Van Leeuwenhoek ; 117(1): 94, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954064

RESUMO

The Aeolian archipelago is known worldwide for its volcanic activity and hydrothermal emissions, of mainly carbon dioxide and hydrogen sulfide. Hydrogen, methane, and carbon monoxide are minor components of these emissions which together can feed large quantities of bacteria and archaea that do contribute to the removal of these notorious greenhouse gases. Here we analyzed the metagenome of samples taken from the Levante bay on Vulcano Island, Italy. Using a gene-centric approach, the hydrothermal vent community appeared to be dominated by Proteobacteria, and Sulfurimonas was the most abundant genus. Metabolic reconstructions highlight a prominent role of formaldehyde oxidation and the reverse TCA cycle in carbon fixation. [NiFe]-hydrogenases seemed to constitute the preferred strategy to oxidize H2, indicating that besides H2S, H2 could be an essential electron donor in this system. Moreover, the sulfur cycle analysis showed a high abundance and diversity of sulfate reduction genes underpinning the H2S production. This study covers the diversity and metabolic potential of the microbial soil community in Levante bay and adds to our understanding of the biogeochemistry of volcanic ecosystems.


Assuntos
Hidrogênio , Metagenoma , Metano , Microbiologia do Solo , Enxofre , Metano/metabolismo , Hidrogênio/metabolismo , Itália , Enxofre/metabolismo , Archaea/genética , Archaea/classificação , Archaea/metabolismo , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Fontes Hidrotermais/microbiologia , Ilhas , Filogenia
2.
Sci Rep ; 14(1): 15465, 2024 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-38965394

RESUMO

Cliffs contain one of the least known plant communities, which has been overlooked in biodiversity assessments due to the inherent inaccessibility. Our study adopted the unmanned aerial vehicle (UAV) with the telephoto camera to remotely clarify floristic variability across unreachable cliffs. Studied cliffs comprised 17 coastal and 13 inland cliffs in Gageodo of South Korea, among which 9 and 5 cliffs were grazed by the introduced cliff-dwelling goats. The UAV telephotography showed 154 and 166 plant species from coastal and inland cliffs, respectively. Inland cliffs contained more vascular plant species (P < 0.001), increased proportions of fern and woody species (P < 0.05), and decreased proportion of herbaceous species (P < 0.001) than coastal cliffs. It was also found that coastal and inland cliffs differed in the species composition (P < 0.001) rather than taxonomic beta diversity (P = 0.29). Furthermore, grazed coastal cliffs featured the elevated proportions of alien and annual herb species than ungrazed coastal cliffs (P < 0.05). This suggests that coastal cliffs might not be totally immune to grazing if the introduced herbivores are able to access cliff microhabitats; therefore, such anthropogenic introduction of cliff-dwelling herbivores should be excluded to conserve the native cliff plant communities.


Assuntos
Biodiversidade , Plantas , Animais , República da Coreia , Ilhas , Dispositivos Aéreos não Tripulados , Herbivoria , Cabras , Ecossistema
3.
PeerJ ; 12: e17694, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952975

RESUMO

Background: Invasive species are the primary threat to island ecosystems globally and are responsible for approximately two-thirds of all island species extinctions in the past 400 years. Non-native mammals-primarily rats, cats, mongooses, goats, sheep, and pigs-have had devastating impacts on at-risk species and are major factors in population declines and extinctions in Hawai'i. With the development of fencing technology that can exclude all mammalian predators, the focus for some locations in Hawai'i shifted from predator control to local eradication. Methods: This article describes all existing and planned full predator exclusion fences in Hawai'i by documenting the size and design of each fence, the outcomes the predator eradications, maintenance issues at each fence, and the resulting native species responses. Results: Twelve predator exclusion fences were constructed in the Hawaiian Islands from 2011-2023 and six more were planned or under construction; all were for the protection of native seabirds and waterbirds. Fences ranged in length from 304-4,877 m and enclosed 1.2-640 ha. One-third of the 18 fences were peninsula-style with open ends; the remaining two-thirds of the fences were complete enclosures. The purpose of twelve of the fences (67%) was to protect existing bird populations, and six (33%) were initiated for mitigation required under the U.S. Endangered Species Act. Of the six mitigation fences, 83% were for the social attraction of seabirds and one fence was for translocation of seabirds; none of the mitigation fences protected existing bird populations. Rats and mice were present in every predator exclusion fence site; mice were eradicated from five of six sites (83%) where they were targeted and rats (three species) were eradicated from eight of 11 sites (72%). Mongoose, cats, pigs, and deer were eradicated from every site where they were targeted. Predator incursions occurred in every fence. Rat and mouse incursions were in many cases chronic or complete reinvasions, but cat and mongoose incursions were occasional and depended on fence type (i.e., enclosed vs. peninsula). The advent of predator exclusion fencing has resulted in great gains for protecting existing seabirds and waterbirds, which demonstrated dramatic increases in reproductive success and colony growth. With threats from invasive species expected to increase in the future, predator exclusion fencing will become an increasingly important tool in protecting island species.


Assuntos
Espécies Introduzidas , Ilhas , Animais , Havaí , Comportamento Predatório , Conservação dos Recursos Naturais , Ecossistema , Aves
4.
PeerJ ; 12: e17305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952984

RESUMO

Juan Fernández and Desventuradas are two oceanic archipelagos located in the southeastern Pacific Ocean far off the Chilean coast that received protected status as marine parks in 2016. Remoteness and access difficulty contributed to historically poor biodiversity sampling and limited associated research. This is particularly noticeable for bivalves, with most prior regional publications focused on single taxa or un-illustrated checklists. This study investigates marine bivalves collected between the intertidal and 415 m depth during (1) the 1997 IOC97 expedition aboard the M/V Carlos Porter, with special focus on scuba-collected micro-mollusks of both archipelagos, (2) two expeditions by the R/V Anton Bruun (Cruise 12/1965 and Cruise 17/1966), and (3) Cruise 21 of USNS Eltanin under the United States Antarctic Program, which sampled at Juan Fernández in 1965. Also, relevant historical material of the British H.M.S. Challenger Expedition (1873-1876), the Swedish Pacific Expedition (1916-1917), and by German zoologist Ludwig H. Plate (1893-1895) is critically revised. A total of 48 species are recognized and illustrated, including 19 new species (described herein) and six other potentially new species. The presence of two species mentioned in the literature for the region (Aulacomya atra and Saccella cuneata) could not be confirmed. The genera Verticipronus and Halonympha are reported for the first time from the Eastern Pacific, as are Anadara and Condylocardia from Chilean waters. Lectotypes are designated for Arca (Barbatia) platei and Mytilus algosus. These findings double the number of extant bivalve species known from the Juan Fernández and Desventuradas archipelagos, highlighting the lack of attention these islands groups have received in the past. A high percentage of species endemic to one or both archipelagos are recognized herein, accounting for almost 78% of the total. The newly recognized level of bivalve endemism supports the consideration of Juan Fernández and Desventuradas as two different biogeographic units (Provinces or Ecoregions) of the Eastern Pacific Ocean.


Assuntos
Biodiversidade , Bivalves , Animais , Oceano Pacífico , Bivalves/classificação , Bivalves/anatomia & histologia , Chile , Ilhas
5.
Sci Adv ; 10(28): eadm8240, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38996028

RESUMO

Island vertebrates have evolved a number of morphological, physiological, and life history characteristics that set them apart from their mainland relatives. However, to date, the evolution of metabolism and its impact on the vulnerability to extinction of insular vertebrates remains poorly understood. This study used metabolic data from 2813 species of tetrapod vertebrates, including 695 ectothermic and 2118 endothermic species, to reveal that island mammals and birds evolved convergent metabolic strategies toward a slow pace of life. Insularity was associated with shifts toward slower metabolic rates and greater generation lengths in endotherms, while insularity just drove the evolution of longer generation lengths in ectotherms. Notably, a slow pace of life has exacerbated the extinction of insular endemic species in the face of anthropogenic threats. These findings have important implications for understanding physiological adaptations associated with the island syndrome and formulating conservation strategies across taxonomic groups with different metabolic modes.


Assuntos
Evolução Biológica , Extinção Biológica , Ilhas , Animais , Aves/fisiologia , Mamíferos , Filogenia , Efeitos Antropogênicos
6.
Antonie Van Leeuwenhoek ; 117(1): 93, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954062

RESUMO

A Gram-negative, rod-shaped, non-motile, aerobic bacterium, designated as strain TK19101T, was isolated from the intermediate seawater of yellow vent in the shallow-sea hydrothermal system located near Kueishantao Island. The strain was found to grow at 10-40 °C (optimum, 35 °C), at pH 6.0-8.0 (optimum, 7.0), and in 0-5% (w/v) NaCl (optimum, 1%). Strain TK19101T was catalase-positive and oxidase-positive. The predominant fatty acids (> 10%) in strain TK19101T cells were C16:0, summed feature 8 (C18:1 ω6c and/or C18:1 ω7c), and C18:0. The predominant isoprenoid quinone of strain TK19101T was ubiquinone-10. The polar lipids of strain TK19101T comprised phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phospholipid, and unknown polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TK19101T belonged to the genus Mesobacterium. Strain TK19101T exhibited highest 16S rRNA gene sequence similarity value to Mesobacterium pallidum MCCC M24557T (97.48%). The estimated average nucleotide identity and digital DNA-DNA hybridization values between strain TK19101T and the closest related species Mesobacterium pallidum MCCC M24557T were 74.88% and 20.30%, respectively. The DNA G + C content was 63.49 mol%. On the basis of the analysis of 16S rRNA gene sequences, genotypic and phylogenetic data, strain TK19101T has a unique phylogenetic status and represents a novel species of genus Mesobacterium, for which the name Mesobacterium hydrothermale sp. nov. is proposed. The type strain is TK19101T (= MCCC 1K08936T = KCTC 8354T).


Assuntos
Composição de Bases , DNA Bacteriano , Ácidos Graxos , Fontes Hidrotermais , Filogenia , RNA Ribossômico 16S , Água do Mar , RNA Ribossômico 16S/genética , Fontes Hidrotermais/microbiologia , DNA Bacteriano/genética , Ácidos Graxos/análise , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Ilhas , Fosfolipídeos/análise , Análise de Sequência de DNA , China
7.
J Environ Manage ; 365: 121617, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38968896

RESUMO

Suspended particulate matter (SPM) plays a crucial role in assessing the health status of coastal ecosystems. Satellite remote sensing offers an effective approach to investigate the variations and distribution patterns of SPM, with the performance of various satellite retrieval models exhibiting significant spatial heterogeneity. However, there is still limited information on precise remote sensing retrieval algorithms specifically designed for estimating SPM in tropical areas, hindering our ability to monitor the health status of valuable tropical ecological resources. A relatively accurate empirical algorithm (root mean square error = 2.241 mg L-1, mean absolute percentage error = 42.527%) was first developed for the coastal SPM of Hainan Island based on MODIS images and over a decade of field SPM data, which conducted comprehensive comparisons among empirical models, semi-analytical models, and machine learning models. Long-term monitoring from 2003 to 2022 revealed that the average SPM concentration along the coastal wetlands of Hainan Island was 6.848 mg L-1, which displayed a decreasing trend due to government environmental protection regulations (average rate of change of -0.009 mg L-1/year). The seasonal variations in coastal SPM were primarily influenced by sea surface temperature (SST). Spatially, the concentrations of SPM along the southwest coast of Hainan Island were higher in comparison to other waters, which was attributable to sediment types and ocean currents. Further, anthropogenic pressure (e.g., agricultural waste input, vegetation cover) was the main influence on the long-term changes of coastal SPM in Hainan Island, particularly evident in typical tropical ecosystems affected by aquaculture, coastal engineering, and changes in coastal green vegetation. Compared to other typical ecosystems around the globe, the overall health status of SPM along the coast wetlands of Hainan is considered satisfactory. These findings not only establish a robust remote sensing model for long-term SPM monitoring along the coast of Hainan Island, but also provide comprehensive insights into SPM dynamics, thereby contributing to the formulation of future coastal zone management policies.


Assuntos
Monitoramento Ambiental , Ilhas , Material Particulado , Material Particulado/análise , Tecnologia de Sensoriamento Remoto , Ecossistema , Imagens de Satélites , China
8.
Sci Rep ; 14(1): 15734, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977746

RESUMO

Despite a long history of research since Darwin, the mechanism underlying rapid adaptive radiation remains poorly understood. All theories constructed to date require special assumptions, so none can comprehensively explain actual cases found in wide-ranging taxonomic groups. Here, we propose a simple theoretical solution to this problem. Namely, we extend the classical archipelago model of adaptive radiation into a more realistic model by adding one assumption, namely, the evolvability of dispersal ability, which is well supported empirically. Our individual-based simulations with evolvable dispersal ability showed that environmental heterogeneity among islands (or island-like habitats) led to an evolutionary decrease in dispersal ability. However, when islands are rather evenly distributed, as is often the case in actual archipelagos where adaptive radiation has been reported, the decline in dispersal ability that began in some island populations was quickly halted by the continuous influx of immigrants from other islands. The process of reduction in dispersal ability in these island populations was resumed almost synchronously when the dispersal ability began to decrease on the final island, which had maintained high dispersal ability and continued to release migrants for the longest duration. Then, a rapid loss of dispersal ability followed in all island populations. In short, the frequent simultaneous evolution of multiple allopatric incipient species was an inevitable consequence of the properties of ordinary archipelagos in our simulations. This study strongly suggests that the seemingly complex process of rapid radiation is driven by a simple mechanism of evolutionary reduction in dispersal ability.


Assuntos
Evolução Biológica , Ecossistema , Ilhas , Animais , Simulação por Computador
9.
Sci Rep ; 14(1): 15668, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019909

RESUMO

Melastoma (Melastomataceae) includes ca. 100 species across tropical to subtropical regions of Asia and Oceania. The Bonin Islands harbor three endemic taxa: M. tetramerum, M. tetramerum var. pentapetalum, and M. candidum var. alessandrense. Of these, M. tetramerum is critically endangered and faces near extinction in the wild. This study investigates the phylogenetic relationships among these endemic Melastoma species in the Bonin Islands based on the whole chloroplast genome and nuclear SNPs. The results revealed that M. candidum var. alessandrense was placed in the clade of the widespread East Asian M. candidum and has a distinct evolutionary origin from the other two taxa. The population genomics analyses (heterozygosity, rates of deleterious mutations, and numbers and lengths of runs of homozygosity) indicated lower genetic diversity and more vulnerable genomes of endemic Melastoma, especially M. tetramerum var. pentapetalum. M. tetramerum var. pentapetalum is not a target of any protection programs, however, conservation plans might be required for this variety because M. tetramerum var. pentapetalum would have a more vulnerable genome than M. tetramerum, which faces near extinction in the wild. This information can facilitate the development of effective conservation strategies in a precautionary way that anticipates imminent threats to the survival of the species.


Assuntos
Melastomataceae , Filogenia , Melastomataceae/genética , Polimorfismo de Nucleotídeo Único , Espécies em Perigo de Extinção , Genoma de Cloroplastos , Genômica/métodos , Ilhas , Variação Genética , Genoma de Planta
10.
Parasitol Res ; 123(6): 247, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38898308

RESUMO

Introduced species have a major impact on freshwater ecosystems, particularly on islands. Numerous fish species have been introduced in Corsica (Mediterranean island, southern France) as part of planned programs or clandestinely. The introduction of non-native freshwater fish species can have a range of impacts on the recipient ecosystem, including through the co-introduction of its pathogens. A sample of introduced perch Perca fluviatilis Linnaeus, 1758 from the artificial reservoir of Padula was examined following a report of parasites by an angler. The analyses revealed the occurrence of Eustrongylides sp. (Nematoda) and Clinostomum complanatum (Digenea), two zoonotic parasites in P. fluviatilis. Both parasites are reported for the first time in France. Eustrongylides sp. and C. complanatum may have been introduced with their fish intermediate hosts or through their final bird hosts. The occurrence of the two parasites raises concerns from both a veterinary and human health perspective as they can use a wide range of amphibians as intermediate hosts and can be acquired in humans through the consumption of raw or undercooked fish.


Assuntos
Doenças dos Peixes , Espécies Introduzidas , Percas , Animais , França , Doenças dos Peixes/parasitologia , Percas/parasitologia , Trematódeos/isolamento & purificação , Trematódeos/classificação , Zoonoses/parasitologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Ilhas , Humanos
11.
Arch Virol ; 169(7): 136, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847927

RESUMO

Here, we report the first detection of lymphocystis disease virus (LCDV) in Indian glass fish in the Andaman Islands, India. Microscopic examination revealed the presence of whitish clusters of nodules on the fish's skin, fins, and eyes. The histopathology of the nodules revealed typical hypertrophied fibroblasts. Molecular characterization of the major capsid protein (MCP) gene of the virus showed a significant resemblance to known LCDV sequences from Korea and Iran, with 98.92% and 97.85% sequence identity, respectively. Phylogenetic analysis confirmed that the MCP gene sequence of the virus belonged to genotype V. This study represents the first documented case of LCDV in finfish from the Andaman Islands, emphasizing the necessity for continued monitoring and research on the health of aquatic species in this fragile ecosystem.


Assuntos
Proteínas do Capsídeo , Infecções por Vírus de DNA , Doenças dos Peixes , Iridoviridae , Filogenia , Animais , Doenças dos Peixes/virologia , Índia , Iridoviridae/genética , Iridoviridae/isolamento & purificação , Iridoviridae/classificação , Infecções por Vírus de DNA/virologia , Infecções por Vírus de DNA/veterinária , Proteínas do Capsídeo/genética , Peixes/virologia , Genótipo , Ilhas
12.
Sci Rep ; 14(1): 14764, 2024 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926420

RESUMO

Spinner dolphins (Stenella longirostris subsp.) occupy the nearshore waters of several Hawaiian Islands. Due to their constrained behavioral pattern and genetic isolation, they are vulnerable to anthropogenic threats. Their occurrence and behavior are well-described, yet a lack of data on their abundance and survival rates hinders optimal conservation action. Using design-based photo-identification surveys, this study estimated the abundance, apparent survival, and emigration of spinner dolphins off the Wai'anae Coast of O'ahu through multi-state open robust design (MSORD) and POPAN modelling. Eight seasonal field seasons, (two winter, spring, summer, and autumn) each comprised of six surveys of the study area, were completed during two consecutive years. Seasonal abundance estimates derived from the best fitting model ranged from 140 (± 36.8 SE, 95% CI 84-232) to 373 (± 60.0, 95% CI 273-509) individuals and were lowest during winter seasons. The MSORD estimated a survival rate of 0.95 (± 0.02 SE) and a Markovian pattern of temporary emigration. POPAN modelling estimated a super-population size of 633 (± 78 SE, 95% CI 492-798), reflecting the total number of individual dolphins that used the study area during the entire study period. Additional research on circum- and inter-island dolphin movements around and between O'ahu and the Maui Nui region may shed light on both seasonal movement patterns and overall abundance for the O'ahu/4-Islands stock. This work represents the first systematic mark-recapture effort to assess the abundance and survival rates of these highly exposed dolphins, providing valuable insights for conservation and management.


Assuntos
Estações do Ano , Animais , Stenella , Densidade Demográfica , Ilhas , Taxa de Sobrevida , Dinâmica Populacional , Conservação dos Recursos Naturais/métodos
13.
BMC Ecol Evol ; 24(1): 84, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926829

RESUMO

BACKGROUND: Accelerating biodiversity loss necessitates monitoring the potential pathogens of vulnerable species. With a third of New Zealand's avifauna considered at risk of extinction, a greater understanding of the factors that influence microbial transmission in this island ecosystem is needed. We used metatranscriptomics to determine the viruses, as well as other microbial organisms (i.e. the infectomes), of seven bird species, including the once critically endangered black robin (Petroica traversi), on two islands in the remote Chatham Islands archipelago, New Zealand. RESULTS: We identified 19 likely novel avian viruses across nine viral families. Black robins harboured viruses from the Flaviviridae, Herpesviridae, and Picornaviridae, while introduced starlings (Sturnus vulgaris) and migratory seabirds (Procellariiformes) carried viruses from six additional viral families. Potential cross-species virus transmission of a novel passerivirus (family: Picornaviridae) between native (black robins and grey-backed storm petrels) and introduced (starlings) birds was also observed. Additionally, we identified bacterial genera, apicomplexan parasites, as well as a novel megrivirus linked to disease outbreaks in other native New Zealand birds. Notably, island effects were outweighed by host taxonomy as a significant driver of viral composition, even among sedentary birds. CONCLUSIONS: These findings underscore the value of surveillance of avian populations to identify and minimise escalating threats of disease emergence and spread in these island ecosystems. Importantly, they contribute to our understanding of the potential role of introduced and migratory birds in the transmission of microbes and associated diseases, which could impact vulnerable island-endemic species.


Assuntos
Doenças das Aves , Aves , Ilhas , Animais , Nova Zelândia/epidemiologia , Aves/virologia , Doenças das Aves/virologia , Doenças das Aves/transmissão , Doenças das Aves/microbiologia , Doenças das Aves/epidemiologia , Vírus/isolamento & purificação , Vírus/genética , Vírus/classificação , Biodiversidade
14.
Mol Phylogenet Evol ; 198: 108130, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38889862

RESUMO

Unusually for oceanic islands, the granitic Seychelles host multiple lineages of endemic amphibians. This includes an ancient (likely ca. 60 million years) radiation of eight caecilian species, most of which occur on multiple islands.These caecilians have a complicated taxonomic history and their phylogenetic inter-species relationships have been difficult to resolve. Double-digest RAD sequencing (ddRADseq) has been applied extensively to phylogeography and increasingly to phylogenetics but its utility for resolving ancient divergences is less well established. To address this, we applied ddRADseq to generate a genome-wide SNP panel for phylogenomic analyses of the Seychelles caecilians, whose phylogeny has so far not been satisfactorily resolved with traditional DNA markers. Based on 129,154 SNPs, we resolved deep and shallow splits, with strong support. Our findings demonstrate the capability of genome-wide SNPs for evolutionary inference at multiple taxonomic levels and support the recently proposed synonymy of Grandisonia Taylor, 1968 with Hypogeophis Peters, 1879. We revealed three clades of Hypogeophis (large-, medium- and short-bodied) and identify a single origin of the diminutive, stocky-bodied and pointy-snouted phenotype.


Assuntos
Anfíbios , Filogenia , Polimorfismo de Nucleotídeo Único , Animais , Seicheles , Anfíbios/genética , Anfíbios/classificação , Filogeografia , Ilhas , Análise de Sequência de DNA
15.
Am J Primatol ; 86(8): e23636, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38824636

RESUMO

As a central topic in Behavioral Ecology, animal space use involves dynamic responses to social and ecological factors. We collared 22 rhesus macaques (Macaca mulatta) from six groups on Neilingding Island, China, and collected 80,625 hourly fixes over a year. Using this high-resolution location data set, we quantified the macaques' space use at the individual level and tested the ecological constraints model while considering various environmental and human interfering factors. As predicted by the ecological constraints model, macaques in larger groups had longer daily path lengths (DPLs) and larger home ranges. We found an inverted U-shape relationship between mean daily temperatures and DPLs, indicating that macaques traveled farther on mild temperature days, while they decreased DPLs when temperatures were too high or too low. Anthropogenic food subsidies were positively correlated to DPLs, while the effect of rainfall was negative. Macaques decreased their DPLs and core areas when more flowers and less leaves were available, suggesting that macaques shifted their space use patterns to adapt to the seasonal differences in food resources. By applying GPS collars on a large number of individuals living on a small island, we gained valuable insights into within-group exploitation competition in wild rhesus macaques.


Assuntos
Sistemas de Informação Geográfica , Comportamento de Retorno ao Território Vital , Macaca mulatta , Animais , Macaca mulatta/fisiologia , China , Masculino , Feminino , Ecossistema , Temperatura , Estações do Ano , Ilhas
16.
Mar Environ Res ; 199: 106611, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38936260

RESUMO

Reef fish communities are shaped by historical and ecological factors, including abiotic and biotic mechanisms at different spatial scales, determining species composition, abundance and biomass. The oceanic islands in the Mid-Atlantic Ridge (St. Peter and St. Paul's Archipelago - SPSPA, Ascension, and St. Helena), exhibiting differences in community structure along a 14-degree latitudinal and a 10 °C thermal gradient. We investigate the influence of sea surface temperature, area, age, isolation and phosphate on reef fish community structures. Reef fish trophic structure varies significantly across the islands, with planktivores and herbivore-detritivores showing the highest abundances in SPSPA and Ascension, while less abundant in St. Helena, aligning with the thermal gradient. Variations in reef fish community structures were predominantly influenced by thermal regimes, corroborating the expansion of species' thermal niche breadth at higher latitudes and lower temperatures. This study highlights that in addition to biogeographic factors, temperature is pivotal on shaping oceanic island reef fish community structure.


Assuntos
Recifes de Corais , Peixes , Animais , Peixes/fisiologia , Ilhas , Oceano Atlântico , Temperatura , Termotolerância , Biodiversidade
17.
Genome Biol Evol ; 16(7)2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38913571

RESUMO

Dingoes come from an ancient canid lineage that originated in East Asia around 8,000 to 11,000 years BP. As Australia's largest terrestrial predator, dingoes play an important ecological role. A small, protected population exists on a world heritage listed offshore island, K'gari (formerly Fraser Island). Concern regarding the persistence of dingoes on K'gari has risen due to their low genetic diversity and elevated inbreeding levels. However, whole-genome sequence data is lacking from this population. Here, we include five new whole-genome sequences of K'gari dingoes. We analyze a total of 18 whole-genome sequences of dingoes sampled from mainland Australia and K'gari to assess the genomic consequences of their demographic histories. Long (>1 Mb) runs of homozygosity (ROHs)-indicators of inbreeding-are elevated in all sampled dingoes. However, K'gari dingoes showed significantly higher levels of very long ROH (>5 Mb), providing genomic evidence for small population size, isolation, inbreeding, and a strong founder effect. Our results suggest that, despite current levels of inbreeding, the K'gari population is purging strongly deleterious mutations, which, in the absence of further reductions in population size, may facilitate the persistence of small populations despite low genetic diversity and isolation. However, there may be little to no purging of mildly deleterious alleles, which may have important long-term consequences, and should be considered by conservation and management programs.


Assuntos
Endogamia , Ilhas , Animais , Austrália , Efeito Fundador , Variação Genética , Isolamento Reprodutivo , Genética Populacional , Homozigoto , Genoma
18.
Mol Biol Evol ; 41(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38889245

RESUMO

The feral cattle of the subantarctic island of Amsterdam provide an outstanding case study of a large mammalian population that was established by a handful of founders and thrived within a few generations in a seemingly inhospitable environment. Here, we investigated the genetic history and composition of this population using genotyping and sequencing data. Our inference showed an intense but brief founding bottleneck around the late 19th century and revealed contributions from European taurine and Indian Ocean Zebu in the founder ancestry. Comparative analysis of whole-genome sequences further revealed a moderate reduction in genetic diversity despite high levels of inbreeding. The brief and intense bottleneck was associated with high levels of drift, a flattening of the site frequency spectrum and a slight relaxation of purifying selection on mildly deleterious variants. Unlike some populations that have experienced prolonged reductions in effective population size, we did not observe any significant purging of highly deleterious variants. Interestingly, the population's success in the harsh environment can be attributed to preadaptation from their European taurine ancestry, suggesting no strong bioclimatic challenge, and also contradicting evidence for insular dwarfism. Genome scan for footprints of selection uncovered a majority of candidate genes related to nervous system function, likely reflecting rapid feralization driven by behavioral changes and complex social restructuring. The Amsterdam Island cattle offers valuable insights into rapid population establishment, feralization, and genetic adaptation in challenging environments. It also sheds light on the unique genetic legacies of feral populations, raising ethical questions according to conservation efforts.


Assuntos
Seleção Genética , Animais , Bovinos/genética , Países Baixos , Variação Genética , Ilhas , Genética Populacional
19.
J Vector Borne Dis ; 61(2): 220-226, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38922656

RESUMO

BACKGROUND OBJECTIVES: In Port Blair, the capital of Andaman & Nicobar Islands, in the Bay of Bengal, India, there was a sudden increase in fever cases resembling the symptoms of dengue in the monsoon period of 2022. Hence, an investigation was carried out to find out epidemiological and entomological reasons behind the outbreak. METHODS: An entomological survey was carried out in 24 wards of Port Blair Municipal Council (PBMC) area, epidemiological data of last six years (January-December 2017-2021 and January-October 2022) and patient details of the year 2022 were collected. Both the epidemiological and entomological data were analyzed concerning time and place. RESULTS: During this outbreak period tyres (22.4%) came out as a major breeding habitat followed by small discarded materials (17.5%), metal drums (15.3%), and plastic drums (11.7%). In rainy season, peri-domestic breeding (55%) was more than the domestic breeding (45%) habitat. Ae. aegypti had a high preference for indoor large containers (100-1000 L) like plastic tank, metal drum and cement tank whereasAe. albopictus prefers to breed in medium sized plastic container (20-100 L) and outdoor water receptacles like tyres, flower pots, and domestic discarded materials. INTERPRETATION CONCLUSION: By source reduction, indoor space spray and outdoor fogging, vector density was controlled which curtailed the transmission and within eight weeks a decreasing trend of dengue cases was noticed. A regular entomological survey is crucial to know the seasonality and key breeding habitats of the vector for proper planning of vector control.


Assuntos
Aedes , Dengue , Surtos de Doenças , Ecossistema , Mosquitos Vetores , Estações do Ano , Índia/epidemiologia , Dengue/epidemiologia , Dengue/transmissão , Animais , Humanos , Aedes/virologia , Aedes/fisiologia , Mosquitos Vetores/virologia , Feminino , Masculino , Adulto , Adolescente , Adulto Jovem , Criança , Pessoa de Meia-Idade , Ilhas/epidemiologia , Vírus da Dengue , Pré-Escolar
20.
JASA Express Lett ; 4(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38922055

RESUMO

An underwater acoustic recorder was moored off Heard Island from September 2017 through March 2018 to listen for marine mammals. Analysis of data was initially conducted by visual inspection of long-term spectral averages to reveal sounds from sperm whales, Antarctic and pygmy blue whales, fin whales, minke whales, odontocete whistles, and noise from nearby ships. Automated detection of sperm whale clicks revealed they were seldom detected from September through January (n = 35 h) but were detected nearly every day of February and March (n = 684 h). Additional analysis of these detections revealed further diel and demographic patterns.


Assuntos
Acústica , Cachalote , Vocalização Animal , Animais , Cachalote/fisiologia , Vocalização Animal/fisiologia , Ilhas , Cetáceos/fisiologia
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